Cooperative Development of Analytical Methods for Diesel Emissions and Particulates — Solvent Extractables, Aldehydes and Sulfate Methods

The Chemical Characterization Panel of the Coordinating Research Council Air Pollution Research Advisory Committee (CRC-APRAC) In house 1-64 Project Group (CAPI 1-64) conducted an extensive study of analytical methods for measuring diesel exhaust emissions. This report details the procedures developed for three of the non-regulated emissions. The first method, solvent extraction of particulate filters, recommends soxhlet extraction with either methylene chloride or toluene-ethanol, depending on the end use of the extract fraction. The second method involves collection of gas phase aldehydes in an acetonitrile-2, 4-dinitrophenylhydrazine solution followed by HPLC-UV analysis. The third method utilizes ion chromatography for analysis of particulate sulfate content.

Round-robin testing by 18 Chemical Characterization Panel participants established precision and accuracy data that define the engineering applicability of the test methods.